Process for dyeing and printing textile fibers



' Patented Apr-.18,

tern UNITED, srA'rEs PATENT orri'cs walmm; mm, or ormm, am) nunorr'mranammmcn, or r. 'L-

oat-mama, e; assronoas r0 emmm- ANILINE woaxs, mo, 0 xxw xonx, x. r, aooarona'rron or namwaan rnoorss roa' Drama; am; rnnrrme max-rim mansll'o Application fled Inc 1 8, 1930, Serial No. 462,138, and in GermanyJune 19, 1989.

The present invention relates to new indigoid vatdyestufi preparationsand to, the dyeig and printing of textile fibers with thesepreparations.

' Accordmg to the present invention esters of ind oid vat dyestuffscorresponding to the pro able general formula:

soar 0* l wherein R represents the radical of an indig'oid dyestuficontaining an indole ring system, n stands for one of the numbers 1 or 2and wherein the (JO-group is attached to the nitrogen atom of the indolering system of R, obtainable according to the process described in U. S.application Ser. No. 379,879 filed 20th July 1929, are fixed on textilefibers, for example, on cotton fiber for instance by slop-padding orprinting, on wool by acid dyeing or by any other known means. The acidamides of the above formula are obtainable by reacting upon the indigoidvat' dyestufi containing an indole' ring system.

with a benzoic acid sulfo halide in the presence of pyridine or ahomologue thereof under substantially anhydrous conditions at a raturebetween about 80 C. and the boil ng point ofv the reaction mixture,until a test portion is completely soluble in water.

' The ester of the indigoid vat dyestufi fixed upon the fiber is treatedwith alkaline agents whereby the ester is split ofl wholly or part- 1according to the quantity of alkali 'used. Ii is evident, that forwholly saponifying the ester at least the calculated amount of analkaline agent is to be employed, but in practical work an excess of thealkaline agent will advantageously be used. For example, b printing oncotton the acid amide obtainable from indigo and benzoic acid metasulfochloride as described above, steaming the printing in theMather-Flatt apparatus and then drawing it through a bath, containinga.small quantity of, free alkali,for

are'obta'inedT-by impregnating (slop pad a short time, a bright indigoprinting is obtained. In asimilar manner indigo dyemgs be applied to thefiber in the form of their with. copper acetate solution.

;. clear printing of indigo is thus obtained,

ding) cotton with the acidamide, steaming in the Mather-Flatt anddeveloping the dyeing with dilute alkali. In the same manner as indigoitself other indigoid dyestufls can esters. Dyeings can be obtained onwool by dyeing the ester in the presence of formic acld or sulfuricacidand then treating the dyeing for a short time with dilute alkali, or

In contradistinction to 'thesaid sulfuric acid esters of vat dyestufis,the so-called indigosols, which can only be develo d in acid solution,the development can ta e place in the present case by means of alkalineagents.

T e' invention is further illustrated by the following examples,without'being restricted thereto:

Example 1.C0tton is printed with a dyestufi paste prepared according tothe follow- 7 mg directions: Y

41-43 parts-of water 6-4 parts by weight of the dyestufi esterobtainable y reacting upon indigo with benzoic acid-meta-sulfochloride 71n the presence of pyridine at a temperature of about l00110 C. 3 partsby weight of thiodiglycol 50 parts by weight of thickening K I (neutralstarch tragacanth thickening.)

.100 parts by weight of paste.

This printing is steamed for 10 minutes in a Mather-Flatt ap aratus,developed by a short immersion minute) at- 45 G. into a bath, containing50 grams of common salt and 50 ccs. of caustic soda solution of 36 B.per liter. The printing is then acidified and soaped in thecustomarymanner. A

possessing a rather better fastness to boiling than the customary indigoprintings.

Example 2.Cotton is slop-padded in the customary manner with anapproximately 4!-6% solution of the indigo acid amide of Example 1, towhich some tragacanth has been added. After drying and assing for 10minutes through a Matherlatt -apparatus, developin of the-"printings isper-' formed. as descri in Example 1.

Ema m Ze 3.--The acid amide of Example caustic soda solution, 1 is dyeon wool within some 14 hours soa mg.

from a bath, which has been rendered acid n testimony whereof, we afixour signawith about by weight of formic acid or tures. 5 sulfuric acid,the dye bath containing 4% WALTER G.

of dyestufi', calculated on the quantity of RUDOLF IA HEIDENREICH. fiberto be dyed. Then the dyeing is developed on the fiber by a shorttreatment with a little alkali, whereby the original 10 violet dyeing ofthe fiber becomes blue. Al-

ternatively the dyeing can also be developed by treating it for about 10minutes at 55 C. with 250 ccs. of a 1% copper acetate filled up withwater to 1 liters. 15 We claim 1. Process which comprises impregnatingtextile fibers with an ester of an indigoid vat dyestufi having in itsfree form the probable formula 2o Y as 25 wherein R represents theradical of an indigoid vat dyestufi containing an indole ring system, nstands for one of the numbers 1 or 2 and wherein the CO-grou is attachedto the nitrogen atom of the in ole ring system 3 and treating theimpregnated fiber with an es alkali. 2. Process which comprisesimpregnating textile fibers with an ester of an indigoid vat dyestufihaving in its free form the probable s5 formula: I

@oo b (/00 N N to do w 30.x our l 1 6 and treating the impregnated fiberwith an I alkali.

3. Process which comprises printing cot- 60 ton with a dyestuii pastehaving incorporated v therewith a compound corresponding in its freeform to the probable formula:

l N/ \N I ea' I 12::

' steaming the rinting in a. Mather-Flatt ap- 55 paratus, deve oping itin a bath containing It A,

